The currently accepted procedure for left atrial access involves routing a needle called a Brockenbrough needle into the right atrium with the Brockenbrough needle pre-placed within a guiding catheter. The guiding catheter specifically preferred for use with a Brockenbrough needle is called a Mullins catheter or transseptal introducer. The Brockenbrough needle is a long, small diameter punch, generally formed from a stainless steel wire stylet that is surrounded by a stainless steel tube.
The Brockenbrough needle, a relatively rigid structure, is operated by advancing the device, with its stylet wire advanced to blunt the sharp tip, within its guiding catheter through the inferior vena cava and into the superior vena cava. Under fluoroscopic guidance, the Brockenbrough needle, retracted inside the distal tip of the Mullins catheter, is withdrawn caudally into the right atrium until it falls or translates medially into the Fossa Ovalis. The Brockenbrough needle can then be advanced out the tip of the Mullins catheter to punch the cardiac tissue.
A main disadvantage of this system is that the Brockenbrough needle system is pre-curved at its distal end and is relatively rigid. This pre-curving, rigidity, and necessary distal sharpness causes the Brockenbrough needle system to carve material from the interior wall of the otherwise straight guiding catheter when the Brockenbrough needle assembly is inserted therethrough. The material carved from the guide catheter could potentially be released into the cardiovascular system and generate emboli with any number of serious clinical sequelae. Should this embolic catheter material enter the left atrium it could flow into and block important arterial vasculature such as the coronary arteries or cerebrovasculature. Furthermore, advancing a pre-curved, rigid punch through the cardiovascular system is difficult and could potentially damage the vessel wall or any number of significant cardiovascular structures, during the advancement.